Brief summary of the E-ELT project

Extremely Large Telescope
40-m class telescope: largest opticalinfrared telescope in the world.
Segmented primary mirror.
Active optics to maintain collimation
and mirror figure.
Adaptive optics assisted telescope.
Diffraction limited performance.
Wide field of view: 10 arcmin.
Mid-latitude site (Armazones in Chile).
Fast instrument changes.
VLT level of efficiency in operations.
The Science
• Contemporary science:
Exoplanets: radial velocity detections, direct imaging,
transit spectroscopy, proto-planetary disks
Fundamental physics: GR in the strong field limit,
variation of fundamental constants, expansion
history of the Universe
Resolved stellar populations: beyond the
Local Group
The physics of high-redshift galaxies
…and much more!
• Synergies with other top facilities:
LSST and other survey telescopes
• Discovery potential:
Opening new parameter space in terms
of spatial resolution and sensitivity
The E-ELT Project
Top priority of European ground-based astronomy (on Astronet and ESFRI lists).
Cerro Armazones in Chile selected as the E-ELT site in April 2010.
Detailed Design Phase completed in 2011. Construction Proposal published in
Dec 2011.
Instrument Roadmap (Nov 2011): 2 first-light instruments + plan for 1st generation.
Project fully approved in Dec 2012.
Construction started in 2013.
Start of operations early next decade.
Construction cost: 1083 M€ (including first-light instrumentation).
The Telescope
M2: 4.2 m
• Nasmyth telescope with a segmented
primary mirror.
• Novel 5 mirror design to include
adaptive optics in the telescope.
• Classical 3mirror anastigmat + 2 flat
fold mirrors (M4, M5).
M4 (AO):
2.4 m
M5 (TT):
2.6x2.1 m
M3: 3.8 m
Nasmyth focus
M1 (seg): 39.3 m
• Two instrument platforms nearly the size
of tennis courts can host 3 instruments
each + Coudé lab.
• Multiple laser guide stars, launched from
the side.
• Nearly 3000 tonnes of moving structure.
The Mirrors
M1: 39.3 m, 798 hexagonal segments of 1.45 m tip-to-tip: 978 m2 collecting area
M4: 2.4 m, flat, adaptive
6000 to 8000 actuators
M5: 2.6 x 2.1 m, flat,
provides tip-tilt correction
The Dome
Classical design.
Diameter = 86 m, height = 74 m.
~3000 tonnes of steel.
Fully air-conditioned and wind
The Instruments
The telescope can host eight instruments.
2007 – 2010: eight instrument and two
adaptive optics module concept studies
were conducted by the community.
Instrument Roadmap (2011):
o Following recommendations by the E-ELT Science Working Group and
ESO's Scientific Technical Committee two first-light instruments have
been identified: a diffraction-limited near-infrared imager and a single-field
near-infrared wide-band integral field spectrograph.
o The next group (ELT-3, 4 and 5) has been broadly identified as covering
the mid-infrared, as well as multi-object and high-resolution spectroscopy.
o Planet camera and spectrograph on separate track.
o Flexibility is maintained by including an as yet unspecified instrument.
o All concept studies remain in the pool of possible instruments.
Instrument Roadmap
The Site
Following an extensive site testing campaign, involving several sites in Chile,
Morocco, the Canary Islands, Argentina, Mexico, etc, ESO Council selected
Cerro Armazones as the E-ELT site.
Selection criteria: impact on science, outstanding atmosphere, but also
construction and operations logistics (roads, water, electricity, nearby cities, ...).
More information
The science users web pages:
The E-ELT Construction Proposal:
The E-ELT Science Case:
The E-ELT Design Reference Mission:
The public web pages:
Brochures, Posters, etc:
Related flashcards

X-ray telescopes

32 cards

Ultraviolet telescopes

19 cards


13 cards

Radio telescopes

14 cards

Create Flashcards